<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/common/dispatcher/dispatcher.js"></script>
<script src="/common/utils.js"></script>
<script src="../resources/utils.js"></script>
<script src="resources/utils.sub.js"></script>

<meta name="variant" content="?default">
<meta name="variant" content="?bypass_cache=true">
<meta name="variant" content="?prefetch=true">
<meta name="variant" content="?prefetch=true&bypass_cache=true">

<script>
setup(() => assertSpeculationRulesIsSupported());

const searchParams = new URLSearchParams(location.search);
const prefetchEnabled = searchParams.has('prefetch');
const bypassCache = searchParams.has('bypass_cache');

// Header size: https://w3c.github.io/resource-timing/#dom-performanceresourcetiming-transfersize
const headerSize = 300;

promise_test(async t => {
    const agent = await spawnWindow(t);
    // Some meaningless query param to avoid cached response.
    const prefetchUrl =
      bypassCache ? agent.getExecutorURL({ a: "b" }) : agent.getExecutorURL();

    if (prefetchEnabled)
      await agent.forceSinglePrefetch(prefetchUrl);

    await agent.navigate(prefetchUrl);

    if (prefetchEnabled)
      assert_prefetched(await agent.getRequestHeaders(),
        `Prefetch ${prefetchUrl.href} should work.`);
    else
      assert_not_prefetched(await agent.getRequestHeaders(),
        `${prefetchUrl.href} should not be prefetched.`);

    await agent.execute_script(
      () => window.entries = performance.getEntriesByType('navigation'));

    // TODO(crbug/1317756): Currently the initial prefetch request bypasses the
    // HTTP cache. Expand test coverage for cache and cache+revalidation cases.
    //
    // We do not assert the exact size of `resources/executor.sub.html` since it
    // would be a headache to update this test everytime executor.sub.html
    // changes.
    assert_equals(await agent.execute_script(() => window.entries.length), 1,
      'Wrong number of entries');
    const entry =
      await agent.execute_script(() => window.entries[0]);
    const bodySize = entry.encodedBodySize;
    assert_greater_than(bodySize, 0);
    assert_equals(entry.transferSize, headerSize + bodySize);
    assert_equals(entry.decodedBodySize, bodySize);
  }, `PerformanceNavigationTiming.transferSize/encodedBodySize/decodedBodySize test, same origin prefetch.`);
</script>
